Question: Simplify the following expression: $x = \dfrac{n^2 - 2n - 24}{n - 6} $
Solution: First factor the polynomial in the numerator. $ n^2 - 2n - 24 = (n - 6)(n + 4) $ So we can rewrite the expression as: $x = \dfrac{(n - 6)(n + 4)}{n - 6} $ We can divide the numerator and denominator by $(n - 6)$ on condition that $n \neq 6$ Therefore $x = n + 4; n \neq 6$